Ladder structure



Oct. 27, F; D. SHUCK LADDER STRUCTURE Filed April 5, 1941' Patented Oct.27, 1942 UNITED STATES PATENT OFFICE 2,300,018 LADDER. STRUCTURE FrancisD. Shuck, Santa Monica, Calif. Application April 5, 1941, Serial No.387,037

2 Claims.

This invention is a ladder structure and more particularly is a meansfor attaching rungs or rounds to un-notched faces of posts or stiles ofladders.

There is in considerable extent of use a common form of ladder made upof 2 x 4" (two by four inch) wooden posts or stiles and the outer facesof these are mortised at suitable intervals and the ends of wooden rungsare countersunk In such a mortised rung ladder the nails are drivendirectly through the end margins of the rungs and owing to loads imposedand to weathering these wooden rungs soon spit just at the nails or forfull length. Often the splits frequently fall out and leave a full lossof step at that position in the ladder. The present invention has for anobject to provide a device which will enable the safe use of a piece ofscantling of 2 x 3 inch dimension and still come within thespecification for toe space as is required in some localities and toavoid the use of mortised 3 x 4 inch stock for ladder stiles.

Another object of the invention is to provide a simple, low-cost, onepiece stamped-metal box device for the ready reception of the near endof a given flat, wooden rung and whereby to rigidly aflix the rung endin a lapped position of the front face of the stile of the ladder.

Also, an object is to provide a box or hollow cleat member so designedand made that it will firmly clinch inwardly on the top and bottom edgesof the rung so as to greatly reduce the hazard of the rung partiallysplitting or cracking, and to provide for the effective holding of thesplits of a rung as may be due to poor quality of stock or because ofshock or overload.

A further object is to provide a box or cleat in which there isincorporated bite-in edges to reduce the hazard of cutting or scratchingthe hands of individuals having to go up or down the ladder.

Additionally, an object is to provide a box of cleat type havingpartially punched holes for nails and which have tongues at the holesdesigned and constructed to cause th nails to take an inclined pitchfavorable to a tensioning function in securing a box to a stile, runneror post of a ladder and to effectively bind on the interposed rung end.

The invention consists of certain advancements, in the ladder buildingart, as set forth in the ensuing disclosure and having, with the above,additional objects and advantages as hereinafter developed, and whoseconstruction, I

combination and details of means, and the functions involved, will bemade manifest in the following description of the herewith illustrativeembodiment; it being understood that modifications, variations andadaptations may be resorted to within the scope, spirit and principle ofthe invention as it is more particularly claimed presently.

Figure 1 is a perspective of the box or cleat device as applied to afiat rung lapped onto the face of a 2 x 3 inch stile.

Figure 2 is a plan of a blank from which the box is shaped'up.

In mine, and trench, and ditch work a ladder made of posts of 2 x 4 inwood and having one inch thick rungs will stand a very heavy load,especially when back-braced to formation or other supporting agent. If a4-inch deep post is mortised an inch deep to receive the end of the rungthere is left a three-inch toe clearance and in some jurisidictions thisis the minimum; by ordinance or law.

Under conditions prevailing currently it is highly desirable to providea means which enables the legitimat use of smaller dimension of stockfor the ladder posts, and by making a lighter ladder providing a moreeconomical use of ladder nails during installation. The instantinvention accomplishes these purposes and saves the high cost of laborinvolved in the mere job of mortising the 2 x 4 posts or stiles, and ashere shown the device consists of preferably a piece of stamped andshaped sheet-metal the fiat blank of which is shown at B, Fig. 2. Owingto the peculiar structure of the shaped device or cleat C, Fig. 1, itmay be made of quite lightweight sheet metal; the cost of the completecleat or box C being far less than the cost of hand-cutting each mortisein the ladder stile.

The box consists of a central, frontal wall or panel 2 of about the samewidth as a given rung R to be lapped on the front face of the ladderstiles S. Along the outer lateral edge of the panel there is arearwardly bent, end closure or wall 3 to lap over the end face of theapplied rung and of such depth as to lap well back on the outer sideface of its relative stile S. Along the top and bottom margins of thepanel 2 there are rearwardly bent tension limbs or flanges 4A the depthof each of which is a little less then the depth of the applied rung,and these flanges are slightly outwardly inclined so as to facilitateclose nesting of the boxes one in the other, for packing, storing andshipping space and cost economy.

The longitudinal edges of the tension flanges 4 are provided withnailing lips 5 which are bent more or less parallel to the panel and tothe face of the stile.

The box thus has two open sides; one to receive the interposed end of arung R longitudinally and. the outer facing the stile and receiving therung from the back of the box. The panel 2, the end wall 3 and the lips5 are all shown as having V-shaped apertures 6 along intruding V-shapedtongues l the purpose of which tongues is to forcibly direct an insertednail in a somewhat oblique direction such as to place a tensionespecially on the parts 3and 4 as the box is nailed to the stile. Thistoe-nailing pitch of the nails is well known to have a highly efficientfastening eifect.

It will be seen that the closed-end box B here shown will effectivelyhold a rung in place against end shift and up or down play even if thenails are not driven through the panel 2; the lateral closure or wall 3forming a stiffening bracket or brace in the box structure.

To avoid the presentation of raw edges of the box the longitudinalmargins of the parts 2, 3 and 5 are slightly bent in a direction to beeffective to bite into the wood when the fastening nails are driven in.

In application of the box one end of a rung is placed in the box and theassembled rung and box are lapped onto the face of the stile, and. oneor two nails are driven into the lower lip 5, to any suitable degree.Then nails are driven full depth through the upper lip and into thestile. This places some tension on the upper flange 4 to firmly draw therung against the stile. The nails in the lower lip 5 can now be drivenfully home to place the lower flange under full tension.

Nails can now be driven fully home through the front panel 2 and intothe rung and stile, if so desired or they may be omitted. Omission ofthe nails has the advantage that it reduces the tendency to split therung either as a result of puncture by the nails, or because of loadtransferred to the nails when load is placed on the top of a rung. -Inan un-punctured rung its undiminished load capacity is available totransmit the load directly to the bottom flange 4 of the applied box.

Finally nails are driven through the stile-lapping portion of the endclosure 3 to close over the end of the rung and to highly brace theupright front panel 2.

It will be seen that by means of the box B it is possible to make ladderstiles of 2 x 3 inch stock and fully comply with requirements specifyinga legal ladder with a three inch toe clearance.

What is claimed is:

1. A ladder rung fastener consisting of a front wall to lap on the outerface of an applied rung,-

' top and bottom flanges bent rearward from the opposite ends of thesaid Wall and being of slightly less width than the thickness of thegiven rung and nailing lips along the said flanges, the said flangesforming tension parts to hold down the lapped and nailed rung. and alateral wall bent rearwardly from the outer side of the front wall andadapted to cover the rear end of the applied rung and being flxable tothe lateral face of a stile to which the rung is lapped.

2. In a ladder structure; stile members, rung elements lapped on theouter faces thereof, rung end boxes forming pockets to receive the endportions of said rungs, each of said boxes formed with side flanges andan end flange to cover the upper, lower and end faces of the endportions of a rung, the side flanges having nailing lips along the outermargins thereof, and the end flange being of such length as to lap theouter face of a stile to provide a portion for attachment to the stile.

FRANCIS D. SHUCK.

